Flow controller, particularly blowout preventer (BOP) and smart pipe plug (SPP)

ABSTRACT

This flow controlling device is a self regulating, reusable blowout preventer or smart pipe plug by limiting the flow in a pipe to a predetermined volume. 
     This flow controlling device or BOP consists mainly of a tapered compression spring in a pipe. The spring measures the dynamic pressure, get compressed by increasing dynamic pressure and closes simultaneously and gradually the cross section for the flow. It closes automatically the pipe completely at a high pressure spike and opens up again after the pressure is normal again. This BOP can be placed deep in the casing of an oil well. It accommodates the drill stem and it works without any human interference. 
     A modified device can be used in any sort of pipe and any flow as a pressure spike preventer (PSP) and also as a smart pipe plug (SPP) manually operated or via remote control.

BACKGROUND OF INVENTION

1. Field of Invention

This flow controlling device is applicable in all kind of pipes to regulate automatically the flow of fluid and gas or a mixture of it. It is specially designed for a new generation of blowout preventers for the gas and oil industry to avoid blow outs and oil gushers like the one in the Gulf of Mexico in 2010.

2. Background Art

Today's BOP's are heavy, complicated and need human interference—and they are build for failures—as reality shows.

The many pipes under cities are not protected against pressure spikes, which can travel along a pipe due to explosions and natural disasters like earthquakes.

3. Advantages of this New BOP

This blowout preventer or BOP works independent from human intervention, independent from the existence of electricity, hydraulic pressure or any other source of energy or information. It takes the information and the energy for operating directly out of the flow of fluid/gas in the pipe.

In can be placed not only on the well head, but also deep in any oil/gas well.

It can also accommodate a turning drill stem.

It is simple and fits in the inside of any pipe.

It can be permanently welded to the pipe or can be made removable.

It can also be pushed deep in an unprepared pipe of an out of control oil well against a strong flow of oil/gas with a self propelled crawler, arrest itself in the wall of the pipe and closes up the pipe.

It can operate autarkic or may remotely controlled.

After a pressure spike it can automatically open up the pipe again.

A modified device can be used in any pipe under cities to prevent high pressure spikes due to explosions, earthquake etc.

SUMMARY OF INVENTION

This device consists mainly of a tapered compression spring, what fits in the pipe with its largest diameter. The pointed cone of the spring is directed against the flow. The tapered spring is able to make both, firstly take the information about the amount of the dynamic pressure directly out of the flow by getting compressed by a too high dynamic pressure and secondly closing the cross section for the flow gradually to zero if the dynamic pressure rises further to dangerous amounts. If the pressure falls again to the predetermined normal amount the spring will open up again allowing the normal predetermined flow.

High pressure spikes due to an explosion, a blow out or “kick” will be stopped and never reach the surface of a well head or the end of a horizontal pipe line.

The spring is just as strong to withstand the dynamic pressure of a normal flow. (This can be adjusted by different materials for the spring and different cross sections of the wire.) If the dynamic pressure raises significantly due to an explosive event or a blow out etc the spring will be compressed and restrict simultaneously the cross section for the flow of fluid/gas. (A sensor for the dynamic pressure and the speed is a spring behind a body. In this case the body is very small or the spring itself, because it is for high forces on the spring.)

This device works like an automated flow controller in a pipe limiting the flow of a fluid—gas mixture also at high pressure and high flow rates in big pipes. It is specially created for the oil industry to prevent catastrophic oil spill, because it offers much more security than today's BOP's.

In case of a pressure spike first the outer coils will be compressed—last the inner coils. This ensures that the closing itself is gradually in the millisecond area not generating another pressure spike in case of an fast explosive event. If the closing of the pipe would be too sharply it would generate an even higher pressure spike. A damping device generates friction for the movement of the spring that it not start swinging and eventually generating a stationary pressure wave in the pipe in resonance with the natural frequency of the pipe. The coils of the spring with a round wire touching each other and pushing each other also to the outside. In the closed phase they rest on stiff radial fins.

Than the forces are transmitted to the wall of the pipe. A strong connection to the wall can be made by the same locking device used by canons withstanding highest pressure spikes. (For unprepared casings this BOP can arrest itself in the wall by 2 sets of sharp claws of movable legs opposing each other and transmitting the forces at a certain angle to the wall. They can also be tightened by a screw.)

This BOP is able to accommodate a rotating drill stem in the center. A compression spring has always a hole in the center. (Only the outer diameter of the pipes from the drill stem must be always the same what is possible if the ends of the pipes get thicker to the inside instead to the outside.)

This BOP deep in the well can be removed for a change of the drill head etc; for instance by another pipe over the drill stem. This pipe works as a tool to turn this BOP in both direction and to push and pull by an interlocking device like a key. Or the drill stem itself has on different spots grooves, keyways and notches etc where a suitable counterpart on the BOP can lock in for a temporary rigid connection for removing and reinstalling the BOP. There could be also several BOP'S deep in the oil well for extra security.

The profile of the spring wire can be adapted to the task. A rectangular profile has better sealing capabilities, can be build overlapping to get a sealing area instead a sealing line by a round profile. It can also get out more force of a certain dynamic pressure to keep hardened steel for a wire material. I some cases may the spring too strong to get compressed by a certain amount of dynamic pressure.

A normal spring in steel will have some leakage. For a complete seal the spring can be coated with hard rubber or plastic materials. If the inner coils are still too strong to close up they can be made gradually thinner in axial direction. For a permanent seal of the pipe regardless of the pressure the spring can be compressed mechanically by a screw.

To get this SPP deep in a pipe against a strong flow a pipe crawler can be used to transport it to the desired spot. It consists of a propeller driven by the flow and turning via a worm gear 8 wheels pushing with sharp spikes in the steel wall of a pipe.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is further explained and illustrated in the following drawings and examples of embodiments:

FIG. 1 is a schematically illustrated axially-sectional view of a smart pipe plug inserted in a pipe 1 with the legs 3 arrested in the wall of the pipe 1 and a tapered spring 6 exposed to a flow in the pipe.

FIG. 2 shows the same smart pipe plug according to FIG. 1 in the same pipe 1 with the spring 6 compressed sealing off the pipe.

FIG. 3 is a top view of the smart pipe plug. (The spring 6 is not shown.)

FIG. 4 is a schematically illustrated axially-sectional view of a blowout preventer (BOP) installed deep in the casing of an oil well with the spring 6 uncompressed.

FIG. 5 shows the same BOP according to FIG. 4 with a compressed spring 6 sealing off the oil well due to a blow out or kick.

FIG. 6 is a cross section and a top view of a pipe crawler, taking energy out of the flow and moving against the flow.

FIG. 7 shows the same pipe crawler pulling a smart pipe plug deep in a pipe against the flow and sealing the pipe 1 off by the compressed spring 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The main part of the smart pipe plug (SPP) in FIG. 1 is the tapered spring 6. At a normal flow there is enough room between the coils for the fluid/gas to flow freely. This spring is designed in this way that it is just strong enough to withstand the normal flow—the normal dynamic pressure. In case of a dynamic pressure spike due to an explosion, kick or a blowout of an oil-well the spring 6 get compressed sealing the pipe. After the high pressure is gone the spring will extend again and allow flow. This works without any external interference. Sometimes a broken end of a pipe must be sealed by hand. This smart pipe plug has a great free cross section and can pushed in a pipe against a strong flow. Guiding fins 5 a and 5 b help to center the SPP to the pipe 1.

At a predetermined depths a cross bar 15 hit the edge of the pipe 1 triggering a release mechanism to arrest the SPP on the wall of the pipe. Attached to the cross bar 15 are guiding fins 5 b and via a steel rope 9 is a ring 8 attached which holds the legs 3 together and the spring 7 compressed until the cross bar hit the pipe. Than the ring 8 releases the legs 3 and the spring 7 pushes the legs with sharp and hard edges in a steel wall. The angle of the legs to the wall is carefully chosen with it they not slip, but get more pressed into the wall the higher the dynamic—and later the static pressure—goes. The spring 7 can never be too strong. The strengths of the spring 6 must be carefully adapted to the specific allowable flow.

This specific SPP in FIG. 1 can also be hand operated. First a nut 13 b is tightened on the thread 12 pressing a massive body 2 on the angled legs and the legs in the wall of the pipe 1 for a firm grip. The force of the screw is between the angled legs and the cross bar 15 resting on the open end of the pipe or between two sets of legs angled in opposite directions.

Than a second nut 13 a on a long threaded rod 14 is tightened compressing the spring 6 via a husk 10 until the pipe is sealed. For easy handling both nuts have radially rods 11.

In FIG. 2 is the same SPP only with the tapered spring 6 totally compressed sealing off the pipe 1.

The spring 6 is able to hold back few thousands of PSI static pressure in any size of pipe. In the compressed pressure state the spring 6 rest in this case on 6 rigid fins. At higher pressure and greater diameters of the pipe a higher number of supporting fins must be applied. Material and profile of the spring 6 can be adapted to the specific task. Steel can be coated with plastic like material to get a better seal. At least on the ends the spring can be squared for a better seal.

In FIG. 3 is a top view of the SPP according to FIG. 1 and FIG. 2. (The spring 6 is not in the drawing.) It is recognizable the great free cross section of this SPP compared with today's on the market. The spring 6 has between all coils the same great cross section. This is important to be able to push the SPP in a pipe against a strong flow.

This SPP in FIG. 4 is made specially for an oil/gas well as a BOP deep in the casing 1 a of the well. It is removable via a locking devise 16 well known by a canon. (This is not a thread, but sections on the circumference only.) It will hold against few thousand of PSI pressure. It can be removed for changing the drill head etc.

A number of massive fins 5 d transmit the high forces (up to a million pound) from the spring 6 a to the casing 1 a. (It is build like a dome of a building.)

The fins 5 c are guiding parts only. They are attached to a ring 19 which is attached to the smallest coil of the spring 6 a sliding together with the spring along a cylindrical part of the body 2 b. A strong inside snap ring provides friction for the spring and works as a shock absorber in case the spring has a tendency to swing. It can also snap in a groove in a compressed state to close the pipe permanently after a blow out in case this would be desired.

The elongated body 2 is hollow to accommodate the drill stem which can freely rotate inside the BOP. At an event like a kick or blowout a ring seal 19 will seal a worn gap between drill stem 18 and BOP.

A pipe 17 over the drill stem 18 will handle the installing and removable of the BOP. This pipe 17 has interlocking members (not shown) to the body 2 and hooks to turn the BOP in both directions and to push or to pull it out again.

FIG. 5 is the same BOP according to FIG. 4, but with a compressed tapered spring 6 a. the rectangular cross section of the spring provides a better sealing capability. Instead of a sealing line at a round profile is there an extended sealing area.

Such a new BOP is simpler than today's BOP's and can be placed deep in the well. They work without any interference from the outside and provide more security against blowouts. The will not destroy the drill stem and allow flow again if the pressure and flow are normal again. Several of such BOP's can be placed deep in any oil/gas well giving the oil/gas industry a new high of security.

FIG. 6 shows a smart pipe plug according to FIG. 2 connected to a pipe crawler. In case an old oil well has not the preinstalled BOP's according to FIG. 3 and FIG. 4 and a bottom kill is desired a smart pipe plug could be eventual still inserted deep in the casing of the oil well by a combination of the smart pipe plug with a pipe crawler. In case the own weight is not enough to overcome a strong flow of a out of control oil well the smart pipe plug needs to be pulled deep down by a crawler attached to it. In this state the ring 8 (seen in FIG. 1) hold the legs 3 together that the SPP has the most possible cross section and the lowest resistance against the dynamic pressure of the flow. At a predetermined depth and certain length of the steel ropes 9 the ring releases the legs, which arrest itself in the wall of the casing. Than a second steel rope 9 a or a longer end attached to the first one pulls a pin 8 a releasing the spring 6 which closes the oil well deep down simply by the dynamic pressure of the flow. A high static pressure will hold is further closed until the pressure is lowered to a predetermined amount. Than the spring 6 opens up again allowing a normal flow of oil. Id desired the spring 6 can also be arrested in the compressed position for a permanent closing of the oil well. In this case an outer snap ring 20 b will snap in the groove 21 where prior the pin 8 a was holding back the spring 6 in the traveling phase.

FIG. 7 shows a sectional view along the center axis of a pipe crawler and a cross section along the line A-A. A propeller 22 is turned by the flow and connected to a shaft 23 which drives two worm gears 24 in a massive body 2 a for 8 wheels touching via hard spikes the wall of a pipe 1 a. To transmit the high torque of the 8 wheels to the wall the hard spikes (not shown) of the wheels are pressed in the wall by springs 26 which deals also with certain bumps etc in the wall like a suspension of a car. The wheels 25 are torque proof connected to shafts 27 with a big gear 28 in the middle but they can slide along the shafts as by cars.

The higher the flow the higher is the power for the movement against the flow. In this way a smart pipe plug could be still inserted deep in an out of control oil well to make a bottom kill.

The spikes or claws from the legs are pressed in the wall with much higher force than the spikes from the wheels of the crawler that the crawler doesn't move any more if the legs are released.

This crawler can also be used for maintenance operations in long pipes like oil pipe lines etc. 

1. Flow controller, particularly blowout preventer (BOP) and smart pipe plug (SPP) mainly consisting of a tapered compression spring, able to seal up the entire cross section of a pipe in a compressed state.
 2. Flow controller, particularly BOP and SPP according to claim 1 with a specific strength of the spring allowing a predetermined normal amount of dynamic pressure against the spring and allowing a normal flow but gradually contracting at a higher flow and restricting the flow by partially closing the cross sections between the coils and sealing up the pipe totally at a catastrophic event with a very high pressure/flow spike and allowing flow again if the pressure goes down to the normal amount again.
 3. Flow controller, particularly BOP and SPP according to claim 1 with a locking devise used by canons to install the removable BOP deep in the casing of an oil well.
 4. Flow controller, particularly BOP and SPP according to claim 1 with a rectangular cross section of the tapered spring.
 5. Flow controller, particularly BOP and SPP according to claim 1 with a number of radial outward spreading legs movable in a big joint of a massive body in the center line of the pipe and with hard pointed ends penetrating the wall of the pipe transmitting high forces to the wall of the pipe with an suitable angle.
 6. Flow controller, particularly BOP and SPP according to claim 1 with a number of rigid radial fins the tapered spring is resting on in a compressed state.
 7. Flow controller, particularly BOP and SPP according to claim 1 with an elongated screw to tighten the angled legs to the wall between two sets of legs in opposite direction or against a cross bar resting on the end of the pipe.
 8. Flow controller, particularly BOP and SPP according to claim 1 with an elongated screw to tighten the tapered spring by hand or remote control sealing the pipe.
 9. Flow controller, particularly BOP and SPP according to claim 1 with a release mechanism for the legs like a ring in a cutout of the legs and a strong spring with a strong outward directed radial force to push the hard pointed ends of the legs in the steel wall.
 10. Flow controller, particularly BOP and SPP according to claim 1 with a massive snap ring to generate friction between the spring and the body in the center for damping a swinging spring.
 11. Flow controller, particularly BOP and SPP according to claim 1 with a hollow body in the center to accommodate a rotating drill stem.
 12. Flow controller, particularly BOP and SPP according to claim 1 with a pipe crawler attached having a propeller and a worm gear connected to 8 wheels with hard spikes penetrating a steel wall and propelling the entire device against the flow. 